I might have read your post on that. I think I also heard it mentioned on the Fox Business show block on a Saturday morning. Maybe they read your posts too;-)
I don't know but this is my original post about a week ago and it has been posted several times since.
There are two types of crude oil, sour oil (heavy oil) and sweet oil (light oil).
Sweet oil is preferred for the production of gasoline and is the more expensive. Sour oil is less expensive but yields less and is more expensive to refine.
Only 30% of the worlds refineries can produce gasoline from heavy oil. 70% of the worlds refineries must have light oil to produce gasoline. The US has already converted 2/3 of its refineries and they can produce gasoline from sour oil. 1/3 remain to be converted. Both SA and Venezuela have made large investments in US refineries to convert them to sour oil operations. The conversions are very expensive and cost billions.
Sweet oil production peaked in 2004 and is in decline and that is what is driving sweet oil price. SA use to produce 40% sour oil and 60% sweet oil. Today they produce 30% sweet oil and 70% sour oil. Virtually all of Venezuela oil is sour oil. If 1000's of tankers of sour oil were stacked at a refinery's door it would be useless if the refinery could only refine sweet oil. The price difference of sweet and sour is sometimes as much as $18 a barrel and has helped keep the price down in the US because of our ability to refine sour oil. However 1/3 of our gasoline must still be refined from sweet oil.
The price of sweet oil will continue to increase from supply and demand until many of the worlds refineries can convert to heavy oil. EU has few heavy oil refineries and must have sweet oil for gasoline. SA is building massive heavy oil refineries and will soon be able to export large amounts of gasoline. China's and Japan's new refineries will use heavy oil.
Of further costs to US gasoline are taxes and a government requirement to use a additive more expensive than gasoline. At the present both Venezuela and SA will supply you with sour crude oil at $50 or less a barrel and would be glad to get rid or it. Sweet oil will continue to go to the highest bidder. Speculators have little to do with the problem other than they insure that you have supply for future use.